1. Field of the Invention
The present invention relates to a switching mode power supply (SMPS) circuit, and more particularly, to an SMPS circuit in which a power factor correction (PFC) part and a standby voltage output part are integrated.
2. Description of the Related Art
A display is a medium that provides information by visually displaying various data on a screen. Due to the advance of digitalization and information, various kinds of displays are introduced and used in various fields. In the past several ten years, Cathode Ray Tube (CRT) has been a main stream of a display market. However, with the development of data communication and Internet, a customer's demand for displays having high performance and high picture quality is increasing and hence the CRT is rapidly replaced with a Flat Panel Display (FPD). A Liquid Crystal Display (LCD) or Plasma Display Panel (PDP), which is under rapid technical development, quickly replaces monitors and TVs, which have been dominated by the CRT. At the same time, the LCD or PDP exploits new application fields, such as notebook computers, mobile phones and vehicle parts, and is used in most applications ranging from small-size products to large-sized products.
Such an LCD or PDP uses an SMPS circuit, as its power supply circuit, which generates various voltages in order to supply a plurality of low voltages.
In a conventional SMPS circuit, a standby voltage output unit is separately provided in order to reduce power consumption in a standby mode. Only the standby voltage output unit is operated, while a Power Factor Correction (PFC) unit and the other output units of a system are not operated.